Repeatability of a dynamic sexual trait: Skin color variation in the Brown Booby (Sula leucogaster)
Por:
Montoya, Bibiana, Flores, Cesar, Torres, Roxana
Publicada:
1 jul 2018
Resumen:
Individual capacity to invest in a reproductive attempt may change over
the breeding season, and such changes may be evaluated by potential
partners through signaling mechanisms. Coloration of bare parts, such as
exposed skin on the throat (gular skin) or feet, is common among avian
species and has the potential to be a dynamic, honest signal of current
condition, especially when such coloration is carotenoid-dependent.
However, few studies have evaluated the repeatability of dynamic
coloration of bare parts in the wild. We determined the presence of
carotenoid pigments (lutein, zeaxanthin, 13-cis-beta-carotene, and
trans-gamma-carotene) in gular skin samples of male and female Brown
Boobies (Sula leucogaster) using high performance liquid chromatography
(HPLC). We then studied color and perceived color variation in the gular
skin of both sexes over the reproductive season, from courtship through
parental care. We estimated color using Endler's segment method and
perceived color using a tetrahedral color space model. Male and female
green chroma was highest during courtship, and, in males, green chroma
declined with capture date. Males' perceived greenness (theta) was
higher during courtship than during the subsequent reproductive stages,
and spectral purity (r achieved) was higher during courtship than
afterward in both sexes. Perceived greenness and spectral purity also
decreased with capture date in males. Male and female gular skin color
and perceived color across the reproductive cycle showed a repeatability
of 1749%. Hence, the presence of carotenoid pigments in gular skin, the
pattern of variation among reproductive stages, and the decline with
capture date suggest that, in the Brown Booby, skin color may be costly
to maintain, its variation can be perceived by other members of the
species, and its intraindividual consistency over time may provide
reliable information about individual's quality.
Filiaciones:
Montoya, Bibiana:
UNAM, Inst Ecol, Lab Conducta Anim, Ciudad De Mexico, Mexico
Univ Autonoma Tlaxcala, CTBC, Tlaxcala, Mexico
Flores, Cesar:
UNAM, Fac Estudios Super Iztacala, UBIPRO, Lab Fisiol Vegetal, Tlalnepantla, Estado De Mexic, Mexico
UNAM, Fac Estudios Super Iztacala, Lab Nacl Salud, Tlalnepantla, Estado De Mexic, Mexico
Torres, Roxana:
UNAM, Inst Ecol, Lab Conducta Anim, Ciudad De Mexico, Mexico
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